A new baby orca wasn't the only interesting discovery researchers made while tracking endangered killer whales.
Researchers aboard a National Oceanic and Atmospheric Administration vessel returned to Oregon earlier this week with a wealth of new data about the whales and their ocean environment.
The information was gained after NOAA Fisheries researchers followed the giant marine mammals for 21 days to find out where they go during the winter, what they eat, and what risks they encounter.
The data and other research will help determine what critical areas offshore need to be protected for the whales, researchers said during a briefing Thursday.
The study came as the National Marine Fisheries Service is considering whether to expand protections for the orcas to include offshore areas from Cape Flattery, Washington, to Point Reyes, California.
The agency has already designated inland waters of Washington as critical to orca conservation.
Using satellite tags, the team tracked the orcas as they swam about 100 miles or so, mostly along the Washington coast and as far south as central Oregon.
The trip that began Feb. 11 provided a unique opportunity to spend up to 24 hours at a time observing the whales, listening to their sounds and collecting samples of what they eat and expel.
Orcas were listed as endangered in 2005. Local and regional efforts began in the 2000s to save them.
The satellite tagging project, research cruises and other efforts are helping scientists fill in the gaps about their travels and diet.
Among the highlights was the discovery of the new baby orca off the coast of Washington in late February, the third such baby documented this winter.
"I never expected to see this, and it was a key finding," said Brad Hanson, wildlife biologist with NOAA's Northwest Fisheries Science Center in Seattle.
For the first time, researchers also observed groups of whales reuniting offshore, he said. The orcas were also seen farther from the coast than before—about 15 miles from Washington and 10 miles from Oregon.
Researchers were also surprised to find the orcas at one point foraging in relatively shallow waters, with a depth of about 26 feet (or 8 meters), near Willapa Bay in southwest Washington.
The scientists were able to get out on a smaller boat to collect fecal samples and fish scales to study what the orcas eat and even which stock of Chinook salmon they prefer.
They also gathered information about the ecosystem where the whales spent their time. While at sea, the scientists collected data on sea surface temperatures, observed the abundance of seabirds in the area, and recorded the sounds the orcas made through a series of hydrophones, or underwater microphones.
"This is such an exciting cruise with so much great data," said Lynne Barre, branch chief for protected resources, West Coast region.
Hanson said there's still more to learn, including whether the movements of the orcas change from one year to the next.
Explore further: Feds spot third baby orca born recently to imperiled pods